Abstract
In this paper, a composite beam subassemblage, which has an elastic-plastic-strain softening concrete slab, is analysed. And the following conclusions are obtained. 1) The behavior of strain at the top and bottom flange at the end of the beam is much effected by the difference of positive and negative moment carrying capacity of composite beam, while it is not much effected by vertical load on the beam and strain softening modulus of concrete slab. And, it is indicated that the relation between the total of end moment (ΣM) of composite beam and strain (ε) at the end of the beam can be predicted on the basis of M-φ relation of steel section. 2) A method of predicting required maximum strain ductility factor at the end of the beam of subassemblages is illustrated, whose strength ratio (β^^-) of composite beam to column is given.
